Forming envelope blanks from a continuously travelling web of paper, or the like



K. STEMMLER Oct. 18, 1966 3,279,290 LLING FORMING ENVELOPE BLANKS FROM A CONTINUOUSLY TRAVE WEB OF PAPER, OR THE LIKE Filed April 6, 1965 2 Sheets-Sheet l United States Patent 3,279,290 FORMING ENVELOPE BLANKS FROM A CON- TINUOUfiLY TRAVELLING WEB OF PAPER, GR THE LIKE Kurt Stemmler, Irlich, near Neuwied Birkenweg, Germany, assignor to Richard Winkler, Rengsdorf ub. Neu- Wied, and Kurt Dunnebier, Gladbach am Birkenhang, Germany Filed Apr. 6, 1965, Ser. No. 446,019 Claims priority, application Germany, Apr. 27, 1964, W 36,669 6 Claims. (Cl. 83-26) This invention relates to a method and means for producing diamond-shaped blanks for letter envelopes, from a web of sheet material, such as paper or the like, unwound from a roll of the sheet material, in which method the cutting and alignment operations take place during the continuous movement of the web and then the blanks after they are separated from the web.

It is known that substantially diamond-shaped blanks for producing envelopes of the type generally used for mailing can be made from a travelling web of paper by cutting the corner cutouts on the travelling web prior to cutting the web crosswise to produce separated blanks; that is, by cutting out the corner cutouts while the web is still in one place and then after the cutouts are made in the web, the web is cut crosswise to form the diamondshaped blanks. And in prior known methods, the corners of the points or tips of the flaps that are subsequently folded over on to the main panel of the blank may, if desired, be cut and rounded off prior to the crosswise cutting of the web to separate the blank from the web (see, for example, U. S. Patents No. 1,265,987 and No. 1,310,922). In those methods, the cutting tools work against counter rollers, or bed rollers, having a hard periphery. The blanks produced in those methods exhibit no deviations between the edges of the diamondshaped blank and the four corner cutouts, provided the edges of the paper web travel without any lateral deflection as it moves in its path of travel in the machine. This is because the cutting tools are seated firmly on rollers which are coupled for rotation with their respective bed rollers (counter rollers) so that there is practically no play and that portion of the web that is to become the blank is still connected to the web before the blank is separated from it so the blank cannot come out of proper position for the cutting operations since it is still an integral part of the web not yet separated from the web. Notwithstanding these apparent advantages, this method has not gained wide acceptance in commercial practice since the tool sets rotating with the rollers can be used only for a single size envelope. Furthermore, the rollertool sets are relatively expensive.

Moreover, the parallelogram-shaped, form-cutting knife for cutting the cutouts in the center of the paper web frequently become clogged in the sharp angles. This, together with the difiiculty of maintaining all the cutting edges of the different knives in dependable cutting condition in continuous operation, results in a large amount of time lost in production. Hence, that method is not used to any substantial extent at the present time because of its uneconomical nature.

Prior art methods are also known wherein the blanks in diamond-shaped form are separated from the travelling web of paper by a linear cut, after which the direction of travel of the separated blanks is changed from the direction of travel of the paper web to the direction of its short axis of symmetry, and thereafter the four corner cutouts are made and also cuts are made on one or more tips of the flap portions of the blank to round off the tips of the flaps. In some instances it required stopping the blank in its path of travel to make the corner cutouts, and in other instances the cutouts were made during the movement of the blank. In machines designed for high speed maximum production, only those methods which do not require stopping the movement of the blank need be considered because the methods and machines which require a stop and go movement are not. competitive with a method in which the blank is continuously moving in its path of travel.

It has heretofore been known that the diamond-shaped blanks can be separated from the paper web by use of a rotatable cutter to make a crosswise cut but the prior constructions for this purpose have a disadvantage or drawback. This is due to the fact that in the prior methods and machines, the diamond-shaped blanks, after separation from the web, do not always lie .in the same relative position, in their path of travel and the position of the successive blanks, is not always the same for successive blanks at the time of the cutting out of the corners. That is, the relative position of the edges of the diamond-shaped blanks as they reach the successive stations where the cutting operations are performed, is not always the same for successive blanks; there being differences from blank to blank either longitudinally or tranverse to the direction of travel or at an angle thereto. It is desirable that the successive blanks lie in the same relative position at each station. But these differences in position of successive blanks, as they move in their path of travel, has not been satisfactorily eliminated by those prior art methods, even when the customary regulating pins, or the like, are utilized. Furthermore, these differences increase upon an increase in the speed of the machines which use the prior art method, with resulting decrease in the quality of the finished envelopes.

It has been the object of the present invention to provide a method and an arrangement of mechanisms which avoid the above mentioned disadvantages and which permit the economical, high-speed production of the diamondshaped envelope blanks with corner cutouts, and also, if desired, with the tips of the flaps cut to round them. A feature of the invention is the elimination of the differences in the relative position of the successive blanks at the stations where the cutting operations are performed on successive blanks at high speeds, for example, at a rate as high as a thousand or more blanks per minute.

The object of the invention is achieved by providing an arrangement of the cutting, aligning and moving mechanisms and a method by which the web and the blanks separated therefrom are kept in continuous forward movement from the supply roll to the folding and gluing machine and the various operations are performed in such manner that the rear, or trailing, cutouts of the diamondshaped blanks are cut from the travelling web, and thereafter the blank is separated from the web by a parting cut and thereupon the rate of movement of the blanks is accelerated in the direction of travel of the web and after this accelerated movement the direction of the path of travel is changed, followed by an aligning of the blank by utilizing the rear corner cutouts, and after said aligning step, the blanks are moved forward in properly registered position and the front (or leading) corner cutouts are made and also such further cuts as may be desired at the tips of the flaps. It is significant to note that even at maximum output speed of the blank forming machine, the front (or leading) corner cutouts are made at precise positions, both with respect to the previously cut rear (or trailing) corner cutouts and with respect to the edges of the diamond-shaped blanks.

Up to the rotary crosswise-cutter, which is to be used for cutting the web to separate the blanks therefrom, the peripheral speed of all of the cutting tools used to carry out the method of the invention must be the same as the a linear speed of the travelling paper. However, the crosswise cutter is moved at a somewhat greater speed than the rate of advance of the web so as to insure the desired shearing action. Adjustable guide means may be provided for maintaining the web. in its desired advancing movement up to and through the crosswise cutter means. After passing through the cutting roller which carries the knife which cuts the web crosswise, means are provided for giving the blank, separated from the web, an accelerated linear speed. Since all other cutting tools operate in synchronism, independently of the length of the format of the blank (that is, the length in the direction of travel of the paper web), the cutters need only be adjusted on their rolls. It will be understood that for a different length of the format of the blank the only change in the mechanism required is a change to a rotary cutter for forming the corner cutouts which is of appropriate size. If it is desired to avoid the necessity of change of rotary cutters then in accordance with a variant of the method, the diamond-shaped blank may first be cut from the web of paper, then the separated blank accelerated to the synchronization speed; the succesion of blanks aligned and then all the four corner cutouts may be made as the successive blanks continue in the direction of the travel of the web. It is also possible to arrange the mechanisms to cut the two rear corner cutouts after the blanks are separated from the web and accelerated during their travel in the direction of the web, after which the direction of path of travel of the blanks is changed and the blanks aligned; after which the front corner cutouts are cut as mentioned above. In each of these variants of the method, which are considered to be within the scope of the invention, the blanks are continuously produced in a manner that in the succession of blanks travelling to the envelope folding and gluing machine, there are no de'viations from blank to blank in the position of the four corner cutouts in each blank with reference to its edges.

With the foregoing objects, features and advantages in view, an illustrative embodiment of the invention will now be described in conjunction with the accompanying drawings in which:

FIG. 1 is a view in diagrammatic form to illustrate the operating steps of the method in accordance with the invention;

FIG. 2 is a view of the same nature as FIG. 1 to illustrate the operating steps of a variant method;

FIG. 3 is a plan View, partly in diagrammatical form, to illustrate the mechanisms and their arrangement for performing the steps illustrated in FIG. 1;

FIG. 4 is a view on line 44 of FIG. 3;

FIG. 5 is a view on line 5-5 of FIG. 3; and

FIG. 6 is a view in section of a modified form of corner cutout mechanism.

Referring now to the drawings, the Web of paper 1 is shown as being unwound from a supply roll (not shown) and advanced by conventional means in the direction of arrows 20. The two rear corner cutouts 2, 2a are cut in the web at station A as a first step; these cutouts are positioned adjacent the places where later on the closure flaps are formed. This first step is performed at station A by a cutter mechanism as illustrated in FIGS. 3 and 5. This cuuter mechanism comprises a lower or anvil roller 54, coupled for synchronous rotation with an upper cutter roller 53 on which are adjustably mounted an angular cutter 52 to make a rear corner cut 2a in the body of the web 1 and an angular cutter 51 to make a corner cut 2 at the edge of the web. The rollers at station A are fixed on shafts mounted for rotation in frame members 21, 21a of the machine. They may be geared together by gears 22 and may be driven by suitable driving means, such as a sprocket and chain 23 driven by motor 24. The periph eral speed of rollers 53 and 54 is the same as the lineal speed of the web 1. I

In the second step which is performed at station B on the machine, the blank lb is separated from the web 1 by a cutting mechanism which makes a crosswise cut 3 in the web to separate the blank from the travelling web. This crosswise cutting mechanism, as shown, is a flying cutter comprising a revolving blade 57 fixed to the periphery of cylindrical roller 58, which is mounted on a shaft for rotation about an axis which is angularly adjustable in relation to the frame members 21, 21a depending upon the desired length of the final blank. The revolving cutter blade 57 cooperates with a stationary blade 59 mounted on a holder 60 secured to the angul'arly adjustable frame which carries the roller 58. The radius from the cutting edge of blade 57 to the axis of the roller 58 is greater than the radius of rollers 53, 54. This permits the free passage of the web between the roller 53 and cutter 59 until the blade 57 comes into cutting position.

The shaft 581: which carries roller 58 is connected with the driving connections from motor 24- and in a manner which permits angular adjustment of roller 58 and blade 59 in relation to the direction of the advancing web. Also the rotary cutter arrangement is such that the peripheral speed of the cutter blade 57 is somewhat greater than that at which the web of paper is being advanced.

The means 80, as shown, for adjustment of the angular relationship of the crosswise cutter blade 57, together with blade 59, comprises a bed plate 81 mounted for rotational adjustment about a vertical axis, provided by a post 81a. A pair of oppositely disposed upstanding standards 82, are fixed to the bed plate 81 and carry bearings 82, 82a at their upper ends in which the roller shaft 58a is mounted for rotation. Another pair of upstanding standards 83 fixed to the bed plate have mounted thereon the block 60 which carries the blade 59. By rotation of the bed plate and then clamping it at adjusted position, the cutter roller 58 with its cutter blade 57 and its cooperating blade 59 can, within limits, be adjusted to make the parting cut 3 on the web at any desired angle with reference to the direction of travel of the web. The cutter roller 58 may be driven by any suitable means. As shown, a flexible, rotatable driving cable 84 is secured at one end to roller shaft 58a and at its other end to sprocket shaft 85; this shaft being mounted for rotation in a bearing 86 adjustably mounted along the frame 21. The shaft 85 is rotated by a sprocket 87 fixed to this shaft, the sprocket engaging the endless sprocket chain 27.

In going to the next step at station C, the separated diamond-shaped blank llb is given an accelerated speed in the direction of travel of the web after the blank is sepa rated from the web at the parting line 3. This is accomplished by tWo feed wheels 61, 61a coupled to rotate with a pair of cooperating wheels 62. The shafts 34.9, 31 are mounted for rotation in the frame members. The shafts are connected for synchronous rotation and are driven by sprocket 32 driven by sprocket chain 27. The wheels 61, 61a have segments 61b, 610 having a radius equal to the radius of wheels 62, and segments 61d, 61s, having a radius less than the radius of wheels 62 so that the blank is gripped for forward accelerated movement only when the segments 61b, 61c engage the paper blank. The blank is then carried in the same direction until its leading edge is moved into the bite of the feed wheels at station C, at which station the direction of the path of travel of the blank 1c is changed. Movement of the blank into position is may be accomplished by appropriately selecting the size and location of the wheels 61 and 61a or by the employment of additional advancing means between wheels 61, 61a and station C.

At station C the direction of movement of the blank 1c is changed into a path toward the folding and gluing machine (not shown), i.e., in the direction of arrows 20a. This is accomplished by a pair of rotating wheels 63, 63a and a pair of cooperating Wheels 64 lying below wheels 63 and 63a. The wheels 63, 63a and cooperating wheels 64 are similar in construction to those at station B. They are fixed on shafts 35, 36 mounted for rotation in the frame members of the machine and are geared together by gearing 37 and are driven by a sprocket gear 38 on shaft 35 in turn driven by a sprocket chain 39 and motor 40. It should be noted here that the wheels 63 and 63a have segments 63b and 630 which have a radius equal to the radius of wheels 64 and segments 63d, 63:; having a radius less than the radius of wheels 64. The peripheral lengths of the segments 63b, 630 are such that when the blank is within their bite the blank 1c is moved in the direction shown in FIGS. 1 and 3, i.e., in the direction of arrows 20a. Upon rotation of the wheels 63, 63a and 64 the blank is then propelled in the direction of arrows 20a to station D, said arrows leading toward the connected folding and gluing machine (not shown) at a linear speed greater than the speed of the web 1.

At station D the blanks are successively aligned longitudinally and tranversely in timed sequence, by suitable mechanism. As shown, this mechanism comprises a pair of wheels 66, 66a fixed on a shaft 41 mounted for rotation in the frame members of the machine, the shaft be ing rotated by a sprocket gear 42 and chain 43 trained over sprocket gear 44 fixed on shaft 35. Mounted on the periphery of wheels 66, 66a are a plurality of pairs of peripherally adjustable pins 65, 6511, those of each pair being oppositely disposed in alignment, parallel with the axis of shaft 41. Fixedly mounted on the frame of the machine are a plurality of arcuate shaped guide members positioned concentrically with the periphery of the wheels 66, 66a. To assist in properly positioning the blanks in the path of the pins 65, 65a between the periphery of wheels 66 and arcuate guides 67, suction means of the character disclosed in Winkler et al. Patent No. 2,944,812 may be employed. As shown, there are five arcuate guide members, three guides 67 inside the vertical planes of the wheels and guides 67a outside the vertical planes of the wheels. Thus there is provided an arcuate slot 45 between the peripheries of the two wheels and the guides 67, 67a. The pairs of pins 65, 65a are adjusted so that after the blank 1b is propelled into the slot, the pins moving with the rotating wheels 66, 66a engage the rear corner cutouts 2, 2a of the blank and register the blank transversely and longitudinally as the blank is propelled through station D. Thus the rear corner cutouts serve as gauge or guide notches. If desired, similar pins mounted upon a pair of spaced endless travelling belts or chains may be utilized to align the blanks at station D.

The blanks are propelled from station D to station E in timed sequence in both transverse and longitudinal alignment and at this station, the two front corner cut- ,outs 5, 5a are made. If desired, any suitable means, such as chains of the character disclosed in Snow U.S. Patent 2,635,520 may be used to advance the blank in alignment and timed sequence to station E. It is significant to note here that there is no deviation at this station in the position of the blanks from blank to blank as the two front corner cutouts are made on successive blanks, with the result that the four corner cutouts are in the same position with reference to the edges of the flaps of the diamond-shaped blanks as each blank is propelled from station E, from which they are delivered in registry and in timed sequence in the direction of arrows 20a to the connected folding and gluing machine (not shown).

The mechanism, as shown, for performing the step of cutting out the front corner cutouts 5, Sal, at station E comprises a cutter in the nature of a flying cutter. On a shaft 46 mounted for rotation in the frame members of the machine are a pair of rollers 69, 69a, adjustably fixed in parallel spaced relation. Fixed to the periphery of the rollers are a pair of profiled oppositely disposed cutter blades 68, 68a, which upon rotation of the rollers, cooperate with a pair of profiled stationary blades 70, 70a, fixed to a rigid bar 47 mounted on the machine frame. The blades are profiled to make the front corner cutouts 5, 5a of appropriate shape to correspond with the rear corner cutouts 2, 2a. And upon rotation of shaft 46 the rotating blades cooperating with the stationary blades, perform the step of cutting the front corner cutouts. The shaft 46 is caused to rotate in synchronism with the mechanisms of stations C and D by means of a sprocket gear 48 and chain 49 which operates from a pair of intergeared shafts 46a, 46b, the latter of which is rotated by a gear 48a over which chain 43 is trained. If desired, the tips of the flaps may be cut off at station E by providing suitable cutter knives.

A variant method is illustrated diagrammatically in FIG. 2. In this method, the web 11 of paper travels continuously from a supply roll (not shown) in the direction indicated by arrows 20. At station F, a diamondshaped blank 11 is cut oif along the cutting line 12 by a rotary cross cutter. On its path from station F the rate of travel of the separated blank is accelerated and propelled to station G where the blank Hg is aligned both laterally and longitudinally in its path of travel by means of a pair of travelling pins 13, 13a such as those previously described, which are adjusted to engage the rear, or trailing edge of the blank; the lateral alignment being accomplished by a fixed guide 14 which is engaged by the side edge of the blank 11g, while the blank is moving. The blank is propelled to station H, where the two rear corner cutouts 15, 15a and also the two front cutouts 16, 16a are made by suitable rotary cutters. The blank is then propelled to the turning station I where the direction of travel of the blank 117' is changed as indicated by arrows 20a. The four corner cutouts 15, 15a and 16, 16a, having been previously made, the blank 11 is propelled to station K where it is aligned laterally and longitudinally by means of travelling pins 17, 17a engaging the rear cutouts 15, 15a, in a suitable mechanism such as shown at station E, FIG. 3. The succession of blanks are then propelled in spaced timed relation and in proper lateral and longitudinal alignment to the folding and gluing machines. :If desired, the tips of the flaps may be cut off at this station, as indicated at 18.

FIG. 6 shows a modified form of rear corner cutout cutting mechanism. It comprises an upper roller 153 having an angle shaped cutter knife 152 adapted to make a rear corner cutout in the body of the web and a cutter knife 151 adapted to make a rear corner cutout at the edge of the web. The cutter roller cooperates with an anvil blade 155 mounted below the web and secured to a mounting block 156 on the frame.

The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. In the claims the term downstream will be understood to mean the direction of travel of the web and blanks toward the folding and gluing machine and the term upstream, the opposite direction.

What is claimed is:

1. A method of manufacturing substantially diamondshaped envelope blanks from a web of paper, or the like, continuously unwound from a roll, wherein all cutting and aligning operations take place during the continuous movement of the web and the blanks separated from the travelling web, to produce diamond-shaped envelope blanks having two rear and two front corner cutouts, which comprises performing the operation of cutting out the two rear corner cutouts from the travelling web, cutting the web crosswise to form separate-d partly finished blanks successively from the web, imparting an acceleration to each blank as it is cut off from the Web and causing the successive blanks after they are separated from the web to travel at a higher speed than the speed of the web, aligning the blanks at said higher speed and then cutting out the two front corner cutouts.

2. A method of producing substantially diamond-shaped envelope blanks from a web of paper, or the like, continuously unwound from a roll, wherein all cutting and aligning operations take place during the continuous movement of the web and the blanks separated from the travelling web, to produce a succession of diamondshaped envelope blanks having two rear and two front corner cutouts, which method comprises continuously feeding the web to a first station in a direction along the center line of said Web and cutting out the two rear corner cutouts at said first station, propelling the travelling web in the same direction to a second station, and at said second station cutting the web crosswise thereby separating a blank from the web and thereupon imparting an acceleration to the separated blank in the same direction, propelling the blank to a third station, at said third station changing the direction of travel of the blank to a path at an angle to the direction of travel of the web and then propelling said blank to a fourth station in said path and at said fourth station aligning the blank longitudinally and transversely and then propelling said blank in timed movement and in registered position to a fifth station, and at said fifth station cutting out the front corner cutouts and then propelling the aligned blank to a folding and gluing machine.

3. A method according to claim 2 in which the transverse and longitudinal alignment of successive blanks at said fourth station is performed by a pair of travelling pins operative in timed relation to engage the two rear corner cutouts and to align and register the blanks while propelling them to said fifth station.

4. In a method of producing substantially diamondshaped envelope blanks from a web of paper, or the like, continuously unwound from a roll, wherein all cutting and aligning operations take place during the continuous movement: of the web and the blanks are separated from the travelling web, to produce envelope blanks having two rear and two front corner cutouts, the steps of cutting the travelling web crosswise to form separate blanks, thereupon accelerating the speed of the separated blanks and aligning the successive travelling blanks transversely and longitudinally in their path of travel, forming four corner cutouts in the individual blanks, two of said cutouts being formed in the rearwardly disposed edges of the final blanks, changing the direction of travel of the blanks to a path at an angle to the direction of travel of the web, and aligning the blanks again longitudinally and transversely by a pair of pins engaging said rearwardly disposed cutouts of successive blanks in timed sequence as they move in their path of travel.

5. In a machine for producing diamond-shaped envelope blanks from a continuously travelling web of paper, said machine having a frame, the combination of a rotary cutter having rear corner cutting knives mounted thereon for cutting a rear corner cutout in the edge of the travelling web and a rear corner cutout in the body of said web at a first station, a rotary cutter mounted on said frame, at a second station downstream from said first station, for cutting said travelling web crosswise to separate a blank from said web, means operative to propel the separated blank at accelerated speed greater than the linear speed of the web, feed mechanism on said frame downstream from said second station operative to propel said blank in the direction of travel of said web and at greater speed than the linear speed of the web, feed mechanism mounted on said frame at a further station downstream operative to receive the blank and to change the direction of travel of said blank and propel it in a direction at an angle from the direction of travel of the web, aligning mechanism mounted for rotation on said frame at a still further station downstream, said aligning mechanism having at least one pair of oppositely disposed pins, travelling in the same direction as said blank and operative to engage said two rear corner cutouts and to align said blank transversely and longitudinally and to propel it in aligned position in its path of travel, and rotary front corner cutout cutting mechanisms mounted for rotation on said frame at a point downstream from said last mentioned station operative to out said front corner cutouts opposite to and registered with said rear corner cutouts.

6. In an apparatus for making diamond-shaped blanks for folding into envelopes, including means for advancing a web of flat material from a source of supply, means for providing corner cutouts in the upstream and downstream edges of the blanks, and cylinder means carrying a knife for making crosswise cuts to sever the individual blanks from the web, the combination which comprises means enabling adjusting of the cylinder means to dispose its knife at different angles to the direction of movement of the web to form blanks of different dimensions, means for advancing the severed blanks into a predetermined position along the line of advance of the web and means for then advancing the severed blanks in a direction perpendicular to the major axis, said last mentioned means including members carrying pins that are advanced at a predetermined speed and are adapted to engage the upstream corner cutouts for advancing the blanks in properly aligned position.

References Cited by the Examiner UNITED STATES PATENTS 2,696,255 12/1954 Heywood 83--91l WILLIAM W. DYER, 111., Primary Examiner.

L. B. TAYLOR, Assistant Examiner. 

1. A METHOD OF MANUFACTURING SUBSTANTIALLY DIAMONDSHAPED ENVELOPE BLANKS FROM A WEB OF PAPER, OR THE LIKE, CONTINUOUSLY UNWOUND FROM A ROLL, WHEREIN ALL CUTTING AND ALIGNING OPERATIONS TAKE PLACE DURING THE CONTINUOUS MOVEMENT OF THE WEB AND THE BLANKS SEPARATED FROM THE TRAVELLING WEB, TO PRODUCE DIAMOND-SHAPED ENVELOPE BLANKS HAVING TWO REAR AND TWO FRONT CORNER CUTOUTS, WHICH COMPRISES PERFORMING THE OPERATION OF CUTTING OUT THE TWO REAR CORNER CUTOUTS FROM THE TRAVELLING WEB, CUTTING THE WEB CROSSWISE TO FORM SEPARATED PARTLY FINISHED BLANKS SUCCESSIVELY FROM THE WEB, IMPARTING AN ACCELERATION TO EACH BLANK AS IT IS CUT OFF FROM THE WEB AND CAUSING THE SUCCESSIVE BLANKS AFTER THEY ARE SEPARATED FROM THE WEB TO TRAVEL AT A HIGHER SPEED THAN THE SPEED OF THE WEB, ALIGNING THE BLANKS AT SAID HIGHER SPEED AND THEN CUTTING OUT THE FRONT CORNER CUTOUTS. 